** Company: ** DRDO

1. The electric field component of a uniform plane wave propagating in a lossless magnetic dielectric

medium is given by E(t,z)=ax 5cos(10^9 t – 20/3 z)V/m. If ?0 represents the intrinsic impedance of the

free space, the corresponding magnetic field component is given by

a) H(t,z)= ay 5/2 ?0 cos(10^9t – 20/3 z)A/m

b) H(t,z)= ay 10/ ?0 cos(10^9t – 20/3 z)A/m

c) H(t,z)= az 5/2 ?0 cos(10^9t – 20/3 z)A/m

d) H(t,z)= az 10/ ?0 cos(10^9t – 20/3 z)A/m

2. The skin depth of a non-magnetic conducting material at 100 MHz is 0.15 mm. The distance which

a plane wave of frequency 10 GHz travels in this material before its amplitude reduces by a factor of

e^-1 is

a) 0.0015 mm b) 0.015 mm c) 0.15 mm d) 1.5 mm

3. A lossless transmission line has a characteristic impedance of 100 ohms and an inductance per unit

length of 1 µH/m. If the line is operated at 1 GHz, the propagation constant ß is

a) 2p rad/m b) 20p/3 rad/m c) 20p rad/m d) 2p *10^5 rad/m

4. When a load resistance Rl is connected to a lossless transmission line of characteristic impedance

75 ohms, it results in a VSWR of 2. The load resistance is

a) 100 ohms b) 75v2 ohms c) 120 ohms d) 150 ohms

5. A two-port network characterized by the S-parameter matrix, [S] = [0.3 L0 0.9 L90

0.9 L90 0.2 L0]

Is

a) both reciprocal and lossless b) reciprocal, but not lossless c) lossless, but not reciprocal d)

neither reciprocal nor lossless

6. A lossless air filled rectangular waveguide has internal dimensions of a cm * b cm. If a=2b and the

cutoff frequency of the TE02 mode is 12 GHz, the cutoff frequency of the dominant mode is

a) 1 GHz b) 3 GHz c) 6 GHz d) 9 GHz

7. A Hertzian dipole antenna is placed at the origin of a coordinate system and it is oriented along zaxis.

In which one of the following planes the radiation pattern of the antenna has a circular shape?

a) x=0 b) y=0 c) z=0 d) ø=45

8. Which one of the following statements is not true?

a) Antenna losses are taken into account in calculating its power gain

b) For an antenna which does not dissipate any power, the directive gain and the power gain are equal

c) Directivity of an antenna is the maximum value of its directive gain

d) The directive gain of a Hertzian dipole is same in all direction

9. The directivity of a half dipole antenna is

a) 1.0 b) 1.5 c) 1.64 d) 2

10. Which one of the following is not true for a step index optical fibre?

a) It can support multiple modes

b) HE11 mode is its lowest order mode

c) The refractive index of the cladding is higher than that of the core

d) At a given wavelength, single mode operation is possible by proper choice of core diameter, core

and cladding refractive indices.

11. Sarnath is situated in the state of

a) MP b) Bihar c) Punjab d) UP

12. Green house effect is due to the increase of atmospheric

a) CO2 level b) SO2 level c) CO level d) N2 level

13. In the month of July, it is winter in

a) New York b) Beijing c) Sydney d) London

14. The chairman of the Planning commission of India is

a) The prime minister b) The vice-president c) The union finance minister d) The union

commerce minister

15. The satellite launch vehicle that placed a number of satellites ito orbit in May 2008 is

a) PSLV-C7 b) PSLV-C8 c) PSLV-C9 d) PSLV-C10

16.DRDO was formed in

a) 1947 b) 1950 c) 1954 d) 1958

17. SAMYUKTA is developed for the use of

a) Navy b) Army c) Air force d) RAC

18. DARL 202 is a variety of

a) pea b) garlic c) capsicum d) tomato

19. TRISHUL is

a) a surface to surface battlefield missile

b) a quick reaction surface to air missile

c) an intermediate range ballistic missile

d) a supersonic cruise missile

20. HUMSA is a

a) sonar b) tank c) mine d) night vision device

21. The value of 1+2i / 3-4i + 2-I / 5i , where i^2 is -1, is

a) -5/2 b) 5/2 c) 2/5 d) -2/5

22. The particular solution of the differential equation d^2y/dx^2 + 2 dy/dx + 5y = 0 satisfying the

conditions y(0)=0 and y’(0)=1 is

a) y=1/2 e^-x cos2x b) y=1/2 e^-x sin4x c) y=1/2 e^-x sin2x d) y=1/2 e^-x cos4x

23. For the vectors A=3i-2j+k and B=2i-k, the value of (A*B).A is

a) 0 b) 1 c) 2 d) 3

24. The orthogonal trajectory of the family of curves x^2-y^2 = a (where a is a constant) and passing

through the point (1,1) is

a) y=-1/x b) y=1/x c) y=-x d) y=x

25. The value of the line integral ? y^2 dx + 2xydy over the curve x=accost, y=asint is

a) 0 b) 1 c) 2 d) 4

26. The n-th partial sum of the infinite series 1/1*2 + 1/2*3 + 1/3*4+……1/n*(n+1)……..

a) 1/n+1 b) n+2/n+1 c) n/n+1 d) n-1/n+1

27. The complex-valued function f(z)=e^z is analytic for

a) no z b) all z c) real z only d) imaginary z only

28. The inverse of the matrix [ cos A sin A

-sin A cos A] is

a) [ -cos A Sin A b) [cos A sin A} c) [cos A -sin A d) [cos A -sin A

sin A cos A] sin A -cos A] -sin A cos A] sin A cos A]

29. Consider the function f(x) defined as

F(x) = 3x-1, x<0
0, x=0
2x+5, x>0

In the following table, List I shows 4 expressions for limits of f(x) and List II indicates the values of the

limits

List I List II

P.Lim x->2 f(x) 1. -1

Q.Lim x->0+ f(x) 2. 9

R.Lim x->0- f(x) 3. -10

S.Lim x->-3 f(x) 4. 5

The correct matches are

a) P-2,Q-4,R-1,S-3 B) P-2,Q-4,R-3,S-1 C) P-4,Q-2,R-1,S-3 D) P-4,Q-2,R-3,S-1

30. Two events A and B with probability 0.5 and 0.7, respectively, have joint probability of 0.4. The

probability that neither A nor B happens is

a) 0.2 b) 0.4 c) 0.6 d) 0.8